That much is clear from Wesport police Detective Jeffrey Majewski’s voice as he talks about Siren, his 5-year-old German shepherd. Someone poisoned Siren, who was being trained as a civilian search-and-rescue dog.

“It was March 31,” Majewski said. “All of a sudden, he didn’t want to move around. When he went to step up on the ottoman, he moaned.”

They took Siren to the vet, and the dog was given an anti-inflammatory drug and sent home.

It got worse.

“On April 1, he didn’t want to move at all,” Majewski said.

They took the dog to Tufts University, to the veterinary school there.

“The MRI showed there was internal bleeding in his back,” Majewski said.

It was painful and untreatable. They had Siren put down.

“When he first had symptoms, we suspected rat poison,” Majewski said. “We didn’t know for sure until the necropsy.”

Rat poison kills by causing massive internal bleeding.

Majewski said the dog did not leave the fenced-in grounds of Majewski’s home unaccompanied.

“I believe someone threw something over the fence,” Majewski said.

And Majewski feels the poisoning may well be connected to his job.

“I don’t think it’s normal for a person to drive around and throw poison into people’s yards at random,” Majewski said. “I think it was intentional.”

Majewski and his girlfriend would have felt bad no matter what kind of dog Siren was, but Siren was training to be a civilian search-and-rescue dog.

“He wasn’t training to be a police K-9,” Majewski said.

Majewski said police dogs are trained to be more aggressive than civilian rescue dogs and are never let off the leash while working.

Civilian rescue dogs, he explained, are let off the leash while they work.

“They’re let off leash, and they range back and forth,” Majewski said.

The dogs are used for a variety of purposes, Majewski said, including locating lost children.

Majewski said he’s still searching for the culprit.

“They could be charged with felony animal cruelly,” Majewski said, adding that the offense carries a possible five-year prison term.

“We’ve gotten a huge amount of support from people,” Majewski said. “The officers of the Westport Police Department are looking for tips.”